A fuse is a protection device. When a short circuit or excessive current fault occurs, it can quickly cut off the power supply and protect the safety of the circuit and electrical equipment.
Please pay attention to the following points when using:
1. The fuse should be connected in series with the line, installed vertically, and installed on each phase line; it is not allowed to install a fuse on the neutral line of a two-phase three-wire or three-phase four-wire circuit.
2. The power input end of the screw fuse should be connected to the center point of the base, and the outlet should be connected to the threaded shell; this fuse is applicable to all vibration locations.
3. When the power load is greater than 60A, and the lighting or electric heating load (220V) is greater than 100A, tubular safety devices should be used.
4. When installing the voltage circuit and electrical control circuit of the watt-hour meter, a control fuse should be installed.
5. Porcelain plug insurance must use qualified lead alloy wire or copper wire. It is forbidden to use multi-strand fuses instead of large fuses.
6. The fuse should be intact, and the contact should be firm and reliable, combined with the maintenance of the power distribution device, check the contact, the discoloration, deformation and aging of the fuse, and replace the fuse if necessary.
7. After selecting the fuse, you must also check whether the selected fuse can protect the wire. If the wire cross section is too small, it should be increased appropriately.
8. The copper cap of the drop-out fuse should be bent to more than 3/4 of the contact on the fusion tube, and the surface of the fusion tube or the melt should be free of damage and cracks.
9. All fuses must not be thickened at will, nor can they be replaced by copper and aluminum wires.
10. For new workshops, apartments and buildings, multiple electric meters must be installed at each entry point. In addition to the main fuse box and the fuse at the entrance, a separate fuse device should be installed for each fuse.